(1) Field of Invention
The present invention relates to a series of novel silicone phosphobetaines which are high foaming low irritation surface active agents that are substantive to fiber and hair. The compounds, because they contain a pendant ionizable phosphate group and a quatarnary amine compound are amphoterics that is they contain both a positive and negative charge in the same molecule. Since the compounds of the present invention are high molecular weight silicone polymers, they have a high degree of oxidative stability, even at elevated temperatures and are nonirritating to skin and eyes. In addition, these compounds are non volatile and exhibit a inverse cloud point. These combination of properties makes these polymers ideally suited for use in personal care applications.
The compounds of the present invention are based upon raw materials which are prepared by the phosphation of a pendant hydroxyl group which is present on a silicone polymer. The phosphated silicone polymers are subject of a copending application upon which this is a continuation in part.
The technology used to produce the phosphobetaines of the present invention is very flexible and allows us to prepare performance tailored molecules for specific applications.
(2) Description of the Arts and Practices
Silicone oils (dimethylpolysiloxane) have been known to be active at the surface of plastic, cellulosic and synthetic fibers as well as paper. Despite the fact that they are lubricants that are stable to oxidation, their high cost and lack of durability has made them cost prohibitive in most application areas. Silicone oils need to be emulsified prior to application. This requires high pressure equipment, surface active agents and generally results in a milky emulsion. Emulsions have experienced stability problems both in terms of freeze thaw instability and upon heating. This has resulted in minimal acceptance of them in commercial products.
The low efficiency of silicone oils is due to the fact that the oil is very water insoluble. Emulsions are generally prepared which contain silicone dispersed in micelles. While this method of application is easier for processing, much of the oil stays in the surfactant micelle and never gets deposited on the fiber. That which does deposit on the fiber surface remains there by hydrophobic binding, not ionic bonding. Since the polydimethylsiloxane is not ionically bonded the effect is very transient. The product is removed with one washing.
Fatty Phosphobetaines have been known since 1974. There are several patents which have issued on this topic.
U.S. Pat. No. 3,856,893 and 3,928,509 both issued to Diery disclose the basic technology used to make phosphobetaines.
Later, amido and imidazoline based phosphobetaines were patented in U.S. Pat. No. 4,209,449 issued in 1980 to Mayhew and O'Lenick. This patent teaches that phosphate quats can be prepared by the reaction of a phosphate salt, three equivalents of epichlorohydrin and in a subsequent step, three equivalents of a tertiary amine.
U.S. Pat. No. 4,215,064 issued in 1980 to Lindemann et al teaches the basic technology that is used for the preparation of amido and imidazoline based phosphobetaines. These compounds can be prepared by the reaction of a phosphate salt, one equivalent of epichlorohydrin and one equivalent of a tertiary amine.
U.S. Pat. No. 4,243,602 issued in 1981 to O'Lenick and Mayhew teaches the basic technology that is used for the preparation of phosphobetaines based upon phosphorous acid salts. These compounds can be prepared by the reaction of a phosphorous acid salt, one equivalent of epichlorohydrin and one equivalent of a tertiary amine.
U.S. Pat. No. 4,261,911 issued in 1981 to Lindemann et al teaches the utilization of phosphobetaines based upon phosphorous acid. These compounds are useful as surfactants.
U.S. Pat. No. 4,283,542 issued in 1981 to O'Lenick and Mayhew teaches the process technology used for the preparation of phosphobetaines. These compounds can be prepared by the reaction of a phosphate salt, one equivalent of epichlorohydrin and one equivalent of a tertiary amine.
U.S. Pat. No. 4,336,386 issued in 1982 to O'Lenick and Mayhew teaches the technology for the preparation of imidazoline derived phosphobetaines based upon phosphorous acid salts. These compounds can be prepared by the reaction of a phosphorous acid salt, one equivalent of epichlorohydrin and one equivalent of an imidazoline.
U.S. Pat. No. 4,503,002 which is related to U.S. Pat. No. 4,209,449 issued in 1985 to Mayhew and O'Lenick teach that phosphate quats can be prepared by the reaction of a phosphate salt, three equivalents of epichlorohydrin and three equivalents of a tertiary amine.
Despite the fact that there was significant patenting of phosphobetaine compounds based upon phosphoric acid salts, phosphorous acids salts, tertiary amines and imidazolines, the technology needed to place a silicone moiety into the molecule and make the compounds of the present invention was not available until the it was discovered that silicone phosphates could be prepared and that they represent starting materials for the preparation of silicone phosphobetaines. Silicone phosphates are the basic raw material used for the preparation of silicone based phosphobetaines. The current application is a continuation in part of the copending patent application which discloses how to make the silicone phosphates. It was also not until the compounds of the present invention that the concept and technology needed to incorporate silicone into the phosphobetaine was created. The beneficial effects of lowering irritation, providing increased substantivity to both hair and skin and antistatic properties were never anticipated by the references.